In the United States, 408 MHz of spectrum from 54 MHz to 806 MHz is allocated for television (TV). Currently, 108 MHz of that spectrum is being redeveloped for commercial operations through auctions and for public safety applications. The remaining 300 MHz of this radio spectrum will, remain dedicated for over-the-air TV operations. Portions of that 300 MHz resource remain unused. The amount and exact frequency of unused spectrum varies from location to location. These unused portions of spectrum are referred to as TV white space (TVWS). The Federal Communications Commission (FCC) is opening these unused TVWS frequencies for a variety of unlicensed uses. Because there are fewer TV stations located outside top metropolitan areas, most of the unoccupied TVWS spectrum is available in low population density or rural areas that tend to be underserved with other broadband options, such as digital subscriber line (DSL) or cable.
The Federal Communications Commission has established rules that allow wireless transmit/receive units (WTRU s) (i.e., hereinafter referred to as white space devices (WSDs)) that are unlicensed to operate in broadcast television spectrum at locations where that spectrum is not used. In order to prevent interference to licensed WSDs operating in the TV bands, the FCC requires TV band WSD databases, also referred to as FCC TV white space databases (FCC-WSDBs), to be created to inform the WSDs of vacant TV channels, register the locations of fixed WSDs, as well as protect locations and channels of incumbent WSDs that are not recorded in the FCC databases.
Several proposals have been made to the FCC for mechanisms and message flows for use in WSDBs to implement three basic functions: a data repository, a data registration process and a query process. However, the WSDBs alone may not achieve good performance.